Hydroxy substituted aliphatic ether derivatives of nitrogen heterocyclics



Patented June 16, 1953 UHUOO [\ETLRLHUE.

umrreo'" STATE-sf PATENT, OFFICE,

HYDROXY' SUBSTITUTED ALIPHATIC"- ETHER- DERIVATIVES O1 NITROGEN- HETERBCYCLIGS Paifl'M: D'owncy, Nitro, W. Va., assignor to Mon-. santo Chemical Gompany, St. Louis, Mo., a cor-' poration of Delaware N Drawing, Application April 27, 1949,

Serial No. 90,052

13.0mm- (Cl. 260-289) where Rds an ortho ar-yleneradical where X is selecttalv from the group consisting of -Sr--,r 0'-; NH--, and-CI-L=CH,=:-, where A is SE1. lected-irom' the-group consistinglof P8P, -Q-#,- and -;-NI-I+-, where X and A are unlike but where X-or- A-lsa sulfur-atom, andwhere R1 .and- R2 are likeouunlike alkylenev groups,. and where n is aninteg-ere The alkylene groups 131. a and R2 may contairi substituentsl such. as "hydroxyl groups.:

These new compounds ;are: particularly useful. asinh-ibitors or regulating agents'in metal pickling baths-and are readily prepared by introducinghydroxyc aliphatio ether radicalsninto such compounds as 2-amino 'benzothiazole, Z-amino- 4-pheny1'benzothiazole;.2-hydroxy benzothiazola 2-hydroxy-4-methyl benzothi-azole, 2-mercapto benzoxazole, 2-mercapto naphthoxazole, 2-mer.- capto-4-phenyl benzoxazole, Z-mercapto benzeimidazole Z-mercapto quinoline,= Z-mercapte-- methyl: quinoline, 'andi theivarious analoguesand homologuesthereoL.

'Iherintroduction of hydroxy aliphatic ethersubstttuenta may be readily efiected-by condens-.:

abovedescribed heterocyclics with compolmdmsuch as, ethylene oxide; propylenemxide z glycide,n epichlorhydrin, trimethylene chlorhy-fv drin,.glycerol alpha chlorhydrin, glycol, glycerine, pol-yglycerine, and the like. Two or more of these reactive compounds-may also be caused to react consecutively. The. condensation advantageouslycarried out in the presence of alkaline reacting agents-or nickel sulfate as catalysts.

Arr-exemplary of the preparation of. the/new compounds the following is illustrative but in nov wise isto be construed as limitative thereof.

Example-1 75.5 parts by-weight (substantially 0.5 mol) of Z-mereapto benzoxazole was dissolvedin 400- partaby weight of a 5% sodium hydroxide S0111?- tion, filtered, and the filtrate placed in a B-neck 2.. flask equipped with a stirrer and thermometer. Upon addition of 40.2 parts by weight (substantially-0.5 mol) of ethylene chlorhydrinthe mix;

was heated with stirringfor about 3 hours at C. A soft brown sticky mass developed which 4 upon separation 'from'the reaction mix was found to-beinsoluble in dilute hydrochloric acid but soluble in benzene and believed to. be the equimolecular condensation product: represented by the formula C-S-OHzCHaOH where n is an integer was obtained. The new compounds were soluble in most organic solvents and solubility in. cold dilute hydrochloric acid increased with increasing yaluesof n.

Example 2 37.8 parts by weight. (substantially 0.25 mol) of 2-hydroxy benzothiazole was dissolved in 200 parts by weight of. a 5% sodium hydroxide solu-. tion, filtered, and the filtrate placed in a 3-neck flask equipped with a stirrer and thermometer. Upon addition of 20.1 parts byweight (substantially 0.25 mol) of ethylene chlorhydrin the mix was heated with stirring for about 3 hours at 60- 65 C. A viscous light brown syrupy substance developed which upon separation fromrthe reaction mix was found to be insoluble in dilute hydrochloric acid but soluble in chloroform and believed to be the equimolecular condensation product represented by the empirical formula C7H4NSO-CH2CH2OH.

Theflequimolecular condensation product. was

i admixed with a small'quantity of potassium hyken, 4

where n is an integer was obtained. The new compounds were soluble in most organic solvents and as the ether content of the molecule increased the solubility of the reaction productsin cold dilute hydrochloric acid increased-also.

Example 3 Propylene oxide was added toax suitablez'reaction vessel containing 2-hydroxy benz'otliiazole and a relatively small amount of potassium hydroxide. The equimolecular reaictionproduct where n is an integer, which were soluble in dilute mineral acids and most organic solvents.

Example 4 22.5 parts by weight (substantially nl5rmo'l) 0f 2-amino benzothiazole was mixed with"0.2 part -by weight of potassium hydroxidetina suitable reaction vessel :and the mass heated-to 140: C. .To the melt,through-an.Alundumthimbleg was added various amounts ofvethylene'mddeanda-series .of liquid reaction products was obtained which may be presented by the general formula 'where n is one or-more' which were completely soluble in cold dilutemineral'acidsand exhibited solubility in most organic solvents.

. -Emample 5 24.0 parts y weight (substantially 0.15 mop of '2 mercapto q'uinoline was mixed with 0.2 part by 'weight of potassium hydroxide 'and the "mass heated to about 200 C. Various amounts-of ethylene oxide were admittedfo themelt through an Alundum thimble and a series of liquid reaction products of the general formula s-omomowmomonn where'n is an integer wasobtained. The'new materials were soluble in"most"orga'n ic solvents arid as n increased the solubility'in-cold mineral acids increased'also.

Example 6 50 parts by weight (substantially 0.32 mol) of 2-mercapto benzimidazole was dissolved in a 5% sodium hydroxide solution, filtered, and the filtrate placed in a 3-neck flask equipped with a stirrer and thermometer. Upon addition of 31.5 parts by weight (substantially 0.33 mol) of trimethylene chlorhydrin the mix was heated with 10 stirring for about three.-hours at 60 -65 C. A .cream colored solid, Mi P. 110.-113 'C.;scleveloped which upon separation from the reaction mix was frfound to be insoluble in dilute hydrochloric acid andbelieved-tolee the equimolecular condensation product represented by the empirical formula 10zHsNiS-OI-IzCI-I2CHzOH.

The equimolecular condensation product was "mixedwithasmallamount of potassium hydrox- =ide, -placedina-suitable reaction vessel, heated above 110 C.,. and thereto was admitted various I amounts of ethylene oxide through an Alundum thimble. A series of liquid reaction products of the general formula where n is an integer was obtained. 'Ihemew materials were soluble in most organic solvents and as the numberof ether groups increased the solubility in cold dilute mineraltacids increased also.

Asaillustrative of the utility of-thenew materials and not limitative thereof, typical examplespfsthe new class of materials were employed inametal pickling process :in amounts .normally'employed under conditions which duplicated, so faras possible, those commonly followed commercial 40 practice. *Portionsnamely 0.012% and 0.03 %by weight based upon the weight of the pickling bath, .of the new class of compounds were incorporated in pickling baths and evaluated in the followin manner:. A test piece of 28 gauge hot'rolled'tin plate steel stock, approximately 4".= x 3" in dimension, was immersed in the pickling bath comprising substantially 3750 0050f a'water solution containing approximately-16% byweight of- 66 sulfuric acid and: a small amount ofzone of 0 the :new compoundsabove described. 'I'hedaem- -perature of .the bath was-maintained atsubstan- 'tially 80 C. iThe steel-test piece after'thoronghly meaning-and pre-pickling forazfew minutes-tin :the absence of: inhibitor. and drying was weighed before immersion in the bath, and after-e40 z'n'inutes picklingizhetest piece wasagain weighed, the difference between? .the -two-z weights; representing' the-metal loss during pickling. 'lfi'hemetal loss compared with-"the metal'losmofasimilarimst piece treated in an analogous: manner butswithout the use ofany inhibitor provides a measure of the inhibiting-value-of thecompound-employed. The results obtained ran-testing typical examples of the preferred class- 'of' materials. are given-in the following table. The metal loss -is-reported as the average of duplicate determinations.

*While 'n.- in'the table below is a=wholenmnber for any given molecu1e,- itisconvenient todesignatenas a -funct-ion-*of-*the= average molecular weight or more particularly the total molecular weight equivalents actually reacted with each "heterocyclicmompound. ncocrdinglm-thevalue of n is -'the "number 'of mols "reacted per meter heterocyclic "-compound- -and "therefore assumes fractional-values.

a sear 116 e 0580 Inhibit" otn mmmmr Metalin Employed Grams I 0.012 .0090 2.86 Completely soluble in p1ckl1ng g3 bath at 80 0. Plckledstrips 9.40 Q0073 cleanand bright.-

SCIH4O (CIHAQ S v I I r 0 C: Q (CYIIHO)QH I I 2 0.012 .0164

I NHCI AO(CSHoO)n 0012 .0130 5.3 00a .0137} 2 N A SCz 4O(C2 4 )H NH N 0 s0=H,o(0,H1o),.H

Blank .7764 Strips pitted.

No inhibitor.

It is obvious from the data set forth that an exceptional class of liquid pickling inhibitors is presented the art. Comparing the loss in weight of the steel test strips to the loss when no inhibitor is employed, it is apparent that a great saving in metal is efiected by the employment ofthese new materials as. pickling inhibitors. 7

While the new compositions wherein n is one possess pickling inhibiting properties, it has been found in general that values of n of 2-25 are to be preferred in amounts normally employed in commercial practice. Compositions containing approximately ether groups have been found both efilcient and economical.

The hydro'xy substituted aliphatic derivatives of the above described heterocyclics wherein n is -40 are slightly soluble in water and possess detergent properties. Further, the new compositions containing 20 or more ether groups may be used as emulsifiers or wetters in non-aqueous systems.

While the invention has been illustrated by a number of specific embodiments of the invention, it will be apparent that many variations may be made from the specific procedures described and from the particular reactants and catalysts employed without departing from the spirit or scope of the invention.

What is claimed is:

1. As a new composition of matter a compound of the structure where R is an ortho arylene radical; where CA x is selected from the group consisting of where R1 and R2 are alkylene groups containing at least two but less than four carbon atoms; and where n is an integer at least 1 but not more than 40.

2. As a new composition of matter a compound of the structure where n is an integer from 2 to 25.

'3. As a new composition or matter a compound of the structure where n is an integer from 2 to 25.

6. As a new composition of matter a compound of the structure where n is an integer from 2 to 25.

7. As a new composition of matter a. compound of the structure where n is approximately 10. v

8. As a new composition of matter a. compound of the structure where n is approximately 10.

9. As a new composition of matter a compound of the structure B-C:H40(C1H40)H where n is approximately 10,

- 10. As a new composition or matter a. compound or the structure o-o-nlomohn .where R1 and R2 are alkylene groups containing more than one but less than four carbon atoms and where n is an integer at least 1 but not more than 40.

11. As a new composition of matter a compound or the structure :where R1 and R2 are alkylene groups containing more than one but less than four carbon atoms and where n is an integer at least 1 but not more I than 40.

12. As a new composition of matter a compound of the structure where n is an integer at least 1 but not more than 40.

13. As a new composition of matter a compound of the structure where n is an integer at least 1 but not more than 40.

PAUL M. DOWNEY.

References Cited in the file of thispatent -UNITED STATES PATENTS L Number Name Date 1,990,963 Teppema "Feb. 12, 1935 2,335,271 Graenacher et a1. Nov. 30, 1943 2,352,078 Coleman et a1. June 20, 1944 2,378,551 Hentrich et a1. June 19, 1945 

1. AS A NEW COMPOSITION OF MATTER A COMPOUND OF THE STRUCTURE 